runtime: minor test cleanup

R=golang-dev, khr, rsc
CC=golang-dev
https://golang.org/cl/11280043
diff --git a/src/pkg/runtime/proc_test.go b/src/pkg/runtime/proc_test.go
index 0e28d5a..29e65da 100644
--- a/src/pkg/runtime/proc_test.go
+++ b/src/pkg/runtime/proc_test.go
@@ -227,7 +227,7 @@
 	stop := make(chan int)
 	go big(stop)
 	for i := 0; i < 3; i++ {
-		time.Sleep(1 * time.Microsecond) // let big start running
+		time.Sleep(10 * time.Microsecond) // let big start running
 		runtime.GC()
 	}
 	close(stop)
@@ -237,7 +237,7 @@
 	n := 0
 	for {
 		// delay so that gc is sure to have asked for a preemption
-		for i := int64(0); i < 1e9; i++ {
+		for i := 0; i < 1e9; i++ {
 			n++
 		}
 
@@ -286,9 +286,6 @@
 	}
 }
 
-func poll() {
-}
-
 func TestSchedLocalQueue(t *testing.T) {
 	runtime.TestSchedLocalQueue1()
 }